Digital Image Overview: Formats, Codecs & Copyright

Introduction

New media is a technological revolution that has changed how society produces and consumes digital content. It has reshaped communication across social, political, and global contexts. Understanding the foundations is essential — including knowledge of file formats, codecs, wrappers, and tools for capturing visual content.

It is equally important to understand that new media has led to changes in legal and social practices related to the preservation of intellectual property rights, such as copyright and patents. This overview covers these concepts alongside commonly used tools and practices for image manipulation, and the copyright essentials every digital creator needs to understand.

Image File Formats

JPEG (.jpg)

JPEG, or Joint Photographic Experts Group, is a lossy format — meaning the image is compressed, resulting in a smaller file. The compression does cause a loss of quality, but it is generally not noticeable. JPEG files are widely used on the internet and are a common format for digital cameras, making them ideal for web use, non-professional prints, email, and presentations.

PNG (.png)

PNG, or Portable Network Graphics, preserves all original data without degradation and was designed to enhance and replace the GIF format. PNG files support 16 million colours, whereas GIFs are limited to 256 — making PNG the superior choice for graphics requiring fine colour detail or transparency.

GIF (.gif)

Graphics Interchange Format files are commonly used for web graphics because they support animations and transparency. However, they are limited to 256 colours, which makes them unsuitable for photographic content.

TIFF (.tif, .tiff)

Tagged Image File Format preserves the original data quality and information, even with compression options. High-quality prints and professional publications use TIFF for its high-quality images and larger file sizes — it is the format of choice when image fidelity cannot be compromised.

Graphics Compression: Lossy vs Lossless

Lossy compression reduces file size by removing some image data, resulting in a permanent loss of quality. In contrast, lossless compression reduces file sizes while preserving all original data, maintaining image quality without degradation. The choice between the two depends entirely on the intended use — web thumbnails can tolerate lossy compression; archival masters cannot.

Video: Wrappers, Codecs & Export Settings

Wrappers and Codecs

A wrapper (also known as a container) is a meta-file format where different data elements and metadata coexist within a single file. A codec is software used to compress and/or decompress digital data. The two work together: the codec handles compression, the wrapper handles packaging.

H.264 (MPEG-4 Part 10 / AVC) is the most widely used standard for video compression — a standard format for recording, compression, and broadcasting high-definition video. Although the newer H.265 is gaining momentum for ultra-high-definition content, H.264 remains the universal baseline.

Platform Export Settings

The three major broadcast platforms — YouTube, Twitch, and Facebook — all use H.264 video codec with AAC audio in an MP4 container. YouTube recommends uploading in SDR at 8 Mbps for 1080p at standard frame rates, and up to 12 Mbps for 60fps content, with AAC-LC audio at 384 kbps stereo.

Twitch recommends CBR (Constant Bit Rate) over VBR (Variable Bit Rate). The problem with VBR is that during temporary pauses, it produces lower bitrates, leading to stream buffering and dropped frames. Twitch uses CBR at 6000 kbps for 1080p60, with a maximum audio bitrate of 160 kbps (AAC).

Facebook similarly recommends H.264 in MP4 or MOV format, supporting resolutions up to 1080p at 60fps, with a video bitrate range of 4500–9000 Kbps and AAC audio at a minimum of 128 kbps. The consistent use of H.264 across all three platforms enables efficient compression and broad compatibility.

Image Manipulation Tools & Techniques

RAW Files

A RAW file is the camera's unprocessed version: the original image data recorded by the sensor, unedited, uncompressed, and saved straight to the memory card. Because it records 12 to 14 bits of information per channel (4,096 to 16,384 shades), it can display much smoother and more detailed colours — far outperforming JPEG files, which are limited to 8 bits (just 256 shades per channel).

Crop, Rotate & Lens Corrections

Cropping allows the removal of unwanted elements and the refinement of a photograph's edges to adjust the aspect ratio or improve composition. It can be used to create a focal point or a dramatic effect. Lens corrections address distortion, vignetting, and chromatic aberration introduced by the optics.

Repairing an Image

When you want to eliminate unwanted parts of an image, you can overlay them with details from other parts of the photo — cloning from one segment to another. In Photoshop, the primary tools for this are the Clone Stamp and the Healing Brush, each suited to different types of repair work.

Tonal Adjustments

Tonal range defines the spectrum of image brightness from the darkest (black) to the lightest (white) pixels. The variation between brightness levels establishes the contrast in an image. Controlling tonal range — through curves, levels, and exposure adjustments — is one of the most fundamental skills in post-processing.

Layers

Digital image editing software such as GIMP or Adobe Photoshop allows users to separate elements of an image into independent layers. This enables adjustment of the colour and geometry of individual components without affecting the rest of the composition — a non-destructive workflow that is essential for professional retouching.

Selection Tools

Image segmentation tools fall into two main categories: Marquee tools, which provide an outline around a section of an image; and colour range selection tools (the "magic wand"), which select portions of an image based on colour range. Together, these tools form the foundation of targeted, precise editing.

Image manipulation — whether photographic, mathematical, or artistic — relies on three core functions: (1) segmenting or masking the image to work only on a defined zone, (2) applying filters or other manipulations, and (3) integrating the modified layers back into the original composition without leaving visible traces of editing.

Copyright & Intellectual Property

There is strong protection for image rights, particularly for photographs of public-domain artwork. Many digital creators face difficulties with copyright restrictions, and legal concerns about appropriation practices are growing. Copyright eligibility depends on whether the work falls within the categories defined by the Copyright, Designs and Patents Act 1988, which includes paintings and sculptures.

You must obtain authorisation from the copyright holder before using an image. However, any image published in a book or journal article before 1927 has entered the public domain and is free to use without copyright issues.

In the US, under specific exemptions such as fair use, it is possible to use copyrighted images without authorisation for good-faith purposes. Copyright grants owners several key rights: the right to reproduce (make copies of the original work), the right to distribute (sell or share copies), and the right to adapt (create new works based on the protected work). Understanding these rights is not optional for anyone working with digital media — it is a professional responsibility.